Raised-center axle and process for forming

Abstract

A cold-formed, raised-center axle for a heavy-duty vehicle includes a central tube having a pair of ends, a pair of spindles attached to the central tube ends, and a wall thickness of from about 0.500 to about 0.625 inches. A hump is formed in the center portion of the tube and includes compressive residual stresses in its bottom portion when the axle is in an in-service position. A method for forming the raised-center axle includes the steps of providing a substantially straight axle, inserting the axle into a press, over-forming a hump in the axle in the direction such that camber is induced in the axle, and forming the axle in a second direction, thereby substantially removing the camber and replacing a detrimental residual stress state in the humped portion of the axle with a beneficial residual stress state.

Dependencies are inferred from the claim text.